The short version
# D4342 Dental Code: Root Planing for 1–3 Teeth
D4342 is the CDT code for scaling and root planing on one to three periodontally involved teeth within one quadrant. It lets the claim match localized disease instead of treating a partial quadrant as four-tooth D4341. The payer still needs bone or attachment loss, tooth-specific probing, and the correct quadrant.
- Bill D4342 when one, two, or three teeth in a quadrant require scaling and root planing for periodontal disease.
- Use D4341 when four or more teeth qualify in that quadrant. Don't count missing spaces or healthy teeth.
- Cigna's 2026 guideline requires qualifying teeth to have pockets of at least 4 mm plus bone loss. Another plan can use a different review threshold.
- Minnesota Medicaid requires authorization, the correct quadrant designator, and no same-day D1110 or D4355.
- In a worked PPO example, a $220 fee becomes a $160 allowable. The plan pays $128 at 80%, the patient owes $32, and the office adjusts $60.
- Attach labeled images and a current periodontal chart that lets the reviewer find each treated tooth quickly.
What is D4342?
D4342 reports therapeutic scaling and root planing for a limited number of diseased teeth in one quadrant. The procedure treats root surfaces affected by periodontitis.
| Fact | D4342 |
|---|---|
| CDT category | Periodontics |
| Unit | One quadrant |
| Tooth threshold | One to three periodontally involved teeth |
| Disease requirement | Periodontitis with supported attachment or bone loss |
| Area reporting | Quadrant designator 10, 20, 30, or 40 |
| Public fee reference | Oregon Medicaid listed $114.56 per quadrant, effective January 1, 2025 |
The ADA's guide to procedures crossing the midline shows how the same treatment span can require D4342 on one side and D4341 on the other after the teeth are divided by quadrant.
When do you bill D4342?
Bill D4342 when periodontal diagnosis and treatment planning identify no more than three qualifying teeth in the reported quadrant.
- Count only teeth that receive root planing for periodontal disease.
- Match probing, bleeding, recession, and attachment findings to each treated tooth.
- Confirm radiographic bone loss or other supported attachment loss.
- Use the quadrant that contains the treated teeth, even when the overall treatment crosses the midline.
- Report another claim line for a second treated quadrant.
The ADA SRP submission guide notes that plans commonly reduce a full-quadrant claim to D4342 when only some teeth meet their criteria.
D4342 vs D4341 and D4346
Diagnosis comes first, then the number of treated teeth in each quadrant.
| D4346 gingivitis scaling | D4342 | D4341 root planing | |
|---|---|---|---|
| Condition | Generalized gingivitis without periodontitis | Periodontitis | Periodontitis |
| Qualifying teeth | Full-mouth inflammation threshold | 1 to 3 per quadrant | 4 or more per quadrant |
| Unit | Full mouth | Quadrant | Quadrant |
| Oregon Medicaid fee | $86.46 | $114.56 | $182.42 |
A quadrant with two diseased teeth and two healthy teeth is D4342, not D4341. The ADA payer examples say bounded spaces don't count either. If another quadrant has four qualifying teeth, D4341 can appear on the same claim with its own quadrant code.
D4346 has a different diagnostic line. Generalized inflammation without attachment or bone loss doesn't become D4342 because only a few teeth bleed more heavily.
What does insurance actually do with D4342?
Cigna's 2026 guidelines allow D4342 when one to three teeth in a quadrant have pockets of 4 mm or deeper plus bone loss. Cigna excludes it when no tooth meets the pocket threshold, images show no bone loss, or the service is incidental to another periodontal procedure.
Delta Dental's submission criteria ask for bitewings or periapicals showing bone levels, periodontal probing from the past 12 months, and sometimes stage-and-grade notes. Minnesota requires prior authorization and the quadrant designator.
- Office fee: $220
- Contracted allowable: $160
- Contractual adjustment: $60
- Plan payment at 80%: $128
- Patient coinsurance: $32
Why does D4342 get denied?
- The listed teeth don't meet the payer's pocket and bone-loss criteria.
- The claim doesn't name the quadrant or lists teeth outside it.
- The radiographs don't show bone height for every treated tooth.
- The history doesn't clear the plan's retreatment limit for that quadrant.
- The plan doesn't allow the same-day procedure combination shown.
Don't accept “no qualifying teeth” before comparing the review with the chart tooth by tooth.
What documentation gets D4342 paid?
- Don't omit the periodontal diagnosis or reported quadrant.
- List each treated tooth number and the sites that require root planing.
- Attach six-site probing with bleeding, recession, and attachment measurements.
- Attach labeled bitewings or periapicals that show the bone level and root surface for each tooth.
- Record calculus, mobility, furcation, and other findings where present.
- Verify prior D4341 and D4342 dates for the same quadrant.
Common questions about D4342
Can D4342 be billed for one tooth?
Yes, it does. D4342 covers one to three periodontally involved teeth within a quadrant. The single tooth still needs the diagnosis, probing, attachment or bone-loss evidence, and root-planing treatment. Put both the tooth number and quadrant on the claim, and keep the treated-site detail in the note.
Can D4342 and D4341 be on the same date?
Yes, when they describe different quadrants and the findings support each tooth count. Don't report both for the same quadrant on the same date. The chart and claim should identify which quadrant received D4341 and which received D4342, with qualifying teeth for each.
Does localized bleeding support D4342?
Bleeding alone doesn't establish periodontitis or root-planing need. Cigna requires pockets at least 4 mm deep plus bone loss. The dentist's diagnosis can include other clinical attachment evidence, but the claim must show why the treated root surfaces need periodontal therapy.
What follows D4342 treatment?
The dentist reevaluates healing and starts periodontal maintenance when appropriate. D4910 can follow active therapy under its clinical rules. The plan can tie D4910 payment to a paid D4342 line, as Minnesota does, so keep the quadrant and completion date in the history.
Count the teeth before submission
Don't file until one to three qualifying teeth and their findings match the quadrant.
Sources
- ADA, Claims Submission: Scaling and Root Planing
- ADA, D4341 and D4342 coding for scaling and root planing
- ADA, quadrant procedures that cross the midline
- Delta Dental, clinical criteria and submission requirements
- Cigna, 2026 dental clinical coverage guidelines
- Minnesota Health Care Programs, Dental Services
- Oregon Medicaid, June 2025 fee schedule
- FAIR Health Consumer, dental cost lookup
CDT codes and nomenclature are copyright © American Dental Association. This guide explains the code in plain language; the current CDT manual is the authoritative source.
